```html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Sweet Celebrations | Birthday Cakes</title>
    <style>
        /* ===== VARIABLES ===== */
        :root {
            --primary: #e91e63;
            --secondary: #9c27b0;
            --accent: #ffab40;
            --light: #f8f4ff;
            --dark: #2e003e;
            --text: #333;
            --transparent-pink: rgba(233, 30, 99, 0.1);
            --shadow: 0 4px 12px rgba(0,0,0,0.1);
            --border-radius: 8px;
        }

        /* ===== BASE STYLES ===== */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            line-height: 1.6;
            color: var(--text);
            background-color: var(--light);
        }

        h1, h2, h3 {
            color: var(--dark);
            line-height: 1.2;
        }

        p {
            margin-bottom: 1rem;
        }

        img {
            max-width: 100%;
            display: block;
        }

        a {
            text-decoration: none;
            color: var(--primary);
        }

        /* ===== LAYOUT ===== */
        .container {
            width: 90%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 1rem;
        }

        section {
            padding: 4rem 0;
        }

        /* ===== HEADER COMPONENT ===== */
        header {
            background-color: #fff;
            box-shadow: var(--shadow);
            position: sticky;
            top: 0;
            z-index: 100;
        }

        .header-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 1rem 0;
        }

        .logo {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--primary);
        }

        nav ul {
            display: flex;
            list-style: none;
            gap: 2rem;
        }

        nav a {
            font-weight: 600;
            padding: 0.5rem 1rem;
            border-radius: var(--border-radius);
            transition: all 0.3s ease;
        }

        nav a:hover,
        nav a:focus {
            background-color: var(--transparent-pink);
        }

        /* ===== HERO SECTION ===== */
        .hero {
            position: relative;
            height: 85vh;
            max-height: 700px;
            display: flex;
            align-items: center;
            background: linear-gradient(rgba(0,0,0,0.3), rgba(0,0,0,0.4)), 
                        url('https://source.unsplash.com/featured/?birthday,cake,decorated') center/cover;
            color: white;
            text-align: center;
        }

        .hero-content {
            max-width: 800px;
            margin: 0 auto;
            padding: 1rem;
        }

        .hero h1 {
            font-size: 3rem;
            margin-bottom: 1rem;
            color: white;
            text-shadow: 0 2px 4px rgba(0,0,0,0.3);
        }

        .hero p {
            font-size: 1.25rem;
            margin-bottom: 2rem;
            max-width: 650px;
        }

        .btn {
            display: inline-block;
            background: var(--accent);
            color: var(--dark);
            font-weight: 700;
            padding: 1rem 2.5rem;
            border-radius: 50px;
            transition: transform 0.3s, box-shadow 0.3s;
            box-shadow: var(--shadow);
        }

        .btn:hover, 
        .btn:focus {
            transform: translateY(-3px);
            box-shadow: 0 6px 16px rgba(0,0,0,0.2);
        }

        /* ===== FEATURES SECTION ===== */
        .features {
            background-color: white;
        }

        .section-title {
            text-align: center;
            margin-bottom: 3rem;
        }

        .section-title h2 {
            font-size: 2.5rem;
            position: relative;
            display: inline-block;
            margin-bottom: 1rem;
        }

        .section-title h2::after {
            content: '';
            position: absolute;
            bottom: -8px;
            left: 50%;
            transform: translateX(-50%);
            width: 80px;
            height: 4px;
            background: var(--primary);
            border-radius: 2px;
        }

        .feature-grid {
            display: grid;
            gap: 2.5rem;
        }

        .feature-card {
            background: #fdf7ff;
            border-radius: var(--border-radius);
            overflow: hidden;
            box-shadow: var(--shadow);
            transition: transform 0.3s;
        }

        .feature-card:hover {
            transform: translateY(-8px);
        }

        .card-content {
            padding: 1.5rem;
        }

        /* ===== FOOTER ===== */
        footer {
            background: var(--dark);
            color: white;
            padding: 3rem 0;
        }

        .footer-container {
            display: grid;
            gap: 3rem;
        }

        .footer-section p {
            margin: 1rem 0;
        }

        .copyright {
            text-align: center;
            padding-top: 2rem;
            border-top: 1px solid rgba(255,255,255,0.1);
        }

        /* ===== RESPONSIVE DESIGN ===== */
        @media screen and (min-width: 768px) {
            .hero h1 {
                font-size: 4rem;
            }
            
            .feature-grid {
                grid-template-columns: repeat(2, 1fr);
            }

            .footer-container {
                grid-template-columns: repeat(3, 1fr);
            }
        }

        @media screen and (min-width: 992px) {
            nav ul {
                gap: 1rem;
            }
            
            .feature-grid {
                grid-template-columns: repeat(3, 1fr);
            }

            .hero-content {
                padding: 1rem 2rem;
            }
        }

        @media screen and (max-width: 767px) {
            nav ul {
                flex-wrap: wrap;
                gap: 0.5rem;
                justify-content: center;
            }

            .section-title h2 {
                font-size: 2rem;
            }
            
            .hero {
                height: 75vh;
            }
        }
    </style>
</head>
<body>
    <!-- Header -->
    <header>
        <div class="container header-container">
            <div class="logo">Sweet Celebrations</div>
            <nav aria-label="Main Navigation">
                <ul>
                    <li><a href="#" aria-current="page">Homepage</a></li>
                    <li><a href="#">Cakes</a></li>
                    <li><a href="#">Order</a></li>
                    <li><a href="#">About</a></li>
                    <li><a href="#">Contact</a></li>
                </ul>
            </nav>
        </div>
    </header>

    <!-- Main Content -->
    <main>
        <!-- Hero Section -->
        <section class="hero" aria-labelledby="hero-heading">
            <div class="container hero-content">
                <h1 id="hero-heading">homepage</h1>
                <p>Discover deliciously crafted birthday cakes that turn your special day into a magical celebration</p>
                <a href="#" class="btn" aria-label="Browse our cake collection">Explore Cakes</a>
            </div>
        </section>

        <!-- Features Section -->
        <section class="features" aria-labelledby="features-heading">
            <div class="container">
                <div class="section-title">
                    <h2 id="features-heading">Our Sweet Specialities</h2>
                </div>
                <div class="feature-grid">
                    <article class="feature-card" aria-labelledby="feature1-heading">
                        <img 
                            src="https://source.unsplash.com/featured/?frosting,cake" 
                            alt="Close up of decorative cake frosting details" 
                            height="240"
                        >
                        <div class="card-content">
                            <h3 id="feature1-heading">Custom Designs</h3>
                            <p>Personalized cakes that match your celebration theme perfectly with edible decorations and vibrant colors.</p>
                        </div>
                    </article>
                    
                    <article class="feature-card" aria-labelledby="feature2-heading">
                        <img 
                            src="https://source.unsplash.com/featured/?birthday,cake,slice" 
                            alt="Slice of layered birthday cake" 
                            height="240"
                        >
                        <div class="card-content">
                            <h3 id="feature2-heading">Premium Ingredients</h3>
                            <p>Handcrafted with high-quality ingredients and baked fresh daily for maximum flavor and texture.</p>
                        </div>
                    </article>
                    
                    <article class="feature-card" aria-labelledby="feature3-heading">
                        <img 
                            src="https://source.unsplash.com/featured/?celebration,cake" 
                            alt="Number shaped birthday cake with candles" 
                            height="240"
                        >
                        <div class="card-content">
                            <h3 id="feature3-heading">Delivery Service</h3>
                            <p>Timely delivery to your doorstep with specialized packaging to keep creations perfect during transit.</p>
                        </div>
                    </article>
                </div>
            </div>
        </section>
    </main>

    <!-- Footer -->
    <footer>
        <div class="container footer-container">
            <div class="footer-section">
                <h3>Sweet Celebrations</h3>
                <p>Creating memorable moments through delicious custom cake artistry for all your special occasions.</p>
            </div>
            
            <div class="footer-section">
                <h3>Contact Us</h3>
                <p>Email: contact@sweetcelebrations.example</p>
                <p>Phone: (555) 123-4567</p>
                <p>Address: 123 Bakery Lane, Pastry City</p>
            </div>
            
            <div class="footer-section">
                <h3>Business Hours</h3>
                <p>Monday-Friday: 9am - 6pm</p>
                <p>Saturday: 10am - 4pm</p>
                <p>Sunday: Closed</p>
            </div>
        </div>
        <div class="container copyright">
            <p>&copy; 2023 Sweet Celebrations. All Rights Reserved.</p>
        </div>
    </footer>
</body>
</html>
```